From Chris Hawkins:
Limousine tooling had been sold to Barrieros in Spain after the last 10 limos were completed in 1965.
Supposedly only 10 '66 limousines were built by Barreiros - Coachbuilders in Spain. Since Chrysler did not oversee this venture none were ever sold via Chrysler in the U.S. Nonetheless, I have driven one of these Spanish limousines and found it as tight and solid as one could wish. I am told, however, that as mysterious as the wiring was in the Ghias, the Spanish limos' electrics are truly incomprehensible.
I have a few clues and conjectures to offer regarding Spanish vs. Italian limousines.
The Spanish Limo I drove began life as a 1965 Imperial. Therein may lie the confusion. All 10 Ghia limousines sold during the 1965 model year began life as 1964's and have pushbutton gearshifts.
The Spanish limo I drove had a 1965 dash with column gearshift. It had 1965 rear bumper inserts and did not have the flat fender peak moldings introduced in 1966. However, it did have a 1966 grill. It was also a couple inches longer than standard and had rear facing jump seats. It was therefore not one of the 20 chassis sent to Ghia in early 1964.
It is conceivable that, similar to the Ghia situation, there was a considerable lead time between acquiring a chassis and finishing the limousine conversion. This lead time would be stretched even further considering Barreiros did not have Ghia's experience with this conversion. The first Spanish limos were very likely built on 1965 chassis' and it was possibly the 1966 model year before the first one was finished. Considering the special order required to get Chrysler to build a sedan body on a convertible frame, I would not be surprised if Chrysler built all 10 chassis at approximately the same time at some point in 1965.
Most Spanish limos surely received 1966 grill updates to correspond with the year they became available for sale. The 1965 limo of unknown origin either was one of the first Spanish ones (still wearing the '65 grill from it's donor chassis) or it is a Ghia. The dashboard and gearshift configuration should be telltale indicators.
Here is another 1965 Imperial Limousine, painted white.